Improving over current DT990 setup.

So I have the Creative Sound Blaster Z, Schiit Magni amplifier, and DT990 250ohm premium. I'm really happy with it as the sound is incredible but I'm curious how much room there really is for improvement. Would a Schiit Vallhalla tube amplifier improve the sound dramatically over the Magni? Also would a Schiit Loki or some other usb DAC improve the audio over my Sound Blaster Z? I do alot of fps gaming so sound positioning is really important, which the Sound Blaster does wonderfully for me on that front. Any help is appreciated, thanks.

So I have the Creative Sound Blaster Z, Schiit Magni amplifier, and DT990 250ohm premium. I'm really happy with it as the sound is incredible but I'm curious how much room there really is for improvement. Would a Schiit Vallhalla tube amplifier improve the sound dramatically over the Magni? Also would a Schiit Loki or some other USB DAC improve the audio over my Sound Blaster Z? I do a lot of fps gaming so sound positioning is really important, which the Sound Blaster does wonderfully for me on that front. Any help is appreciated, thanks.